Polyorganosilsesquioxane and process for preparing the same

ABSTRACT

Provided are polyorganosilsesquioxane and process for preparing the same. The polyorganosilsesquioxane is obtained by various methods including polymerization of 1,3-diorganosiloxane, a precursor that is prepared by using silane compounds as starting materials. The polyorganosilsesquioxane has convenience in handling and controlling the rate of polymerization, and structure of highly regular form, and be imparted high functionality and various characteristics as compared to a conventional polyorganosilsesquioxane.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates topolyorganosilsesquioxane and aprocess for preparing the same, and more particularly, topolyorganosilsesquioxane having silane-based compounds as startingmaterials, and a process for preparing the same.

[0003] 2. Description of the Related Art

[0004] With the development of high-level advanced technology, researchinto high-performance, multi-functional high-technology materials isbeing conducted in various fields. In particular, in research into novelpolymeric materials, much attention has been paid to novelhigh-functional organic polymers, e.g., organic polymers having improvedheat resistance and glass transition temperature (Tg), and technology offorming organic or inorganic hybrid materials, such as an organic andinorganic hybrid complex.

[0005] There are known many existing organic or inorganic hybridmaterials. In particular, due to importance of thermal stability betweenorganic polymer and inorganic polymer, keen attention is focused onpolyorganosilsesquioxane, which is a high-heat-resistance polymer.

[0006] Polyorganosilsesquioxane was first introduced in an article of J.Am. Chem. Soc., 82, 6194 (1960) by Brown et al., and commercialized intrade names of “Glass-resin” and “SST-resin” by Owens Illinois andGelest. However, polyorganosilsesquioxane is not being put intopractical use as industrial material because of difficulties ofcontrolling the polymer structure and adjusting the molecular weightthereof.

[0007] A highly regular ladder form of polyorganosilsesquioxane accountsfor its improved performance properties. Thus, along with development ofnovel starting materials that can easily form a perfect ladder-formstructure, research into condensation methods thereof has been made invarious fields of industry in various ways.

[0008] Among known methods of preparing polyprganosilsesquioxane, arepresentative method is to dehydrate and condense a precursorhydrolyzed product (oligomer), synthesized by hydrolyzingtrichlorosilane or trialkoxysilane in the presence of alkali/acidiccatalyst, thereby easily obtaining a low-molecular weight polymer(having a number-average molecular weight (M_(n)) of 10,000 to 30,000and a degree of dispersion (M_(w)/M_(n)) of 3 to 20.

[0009] A conventional method of preparing polyorganosilsesquioxane usingtrichlorosilane will first be described. Oligomer produced byco-hydrolytic condensation when hydrolyzing trichlorosilane, theoligomer having M_(n) of 1,000 to 2,000 and a polydispersity index value(PDI) of 2 to 5, has a complicated, diverse structure, compared tosilanetriol which is a single structure. In the case of forminghigh-molecular weight oligomer, a three-dimensional network structure iseasily formed by constructural deformity due to the presence ofinter-hydroxy group, and the inherent structure of oligomer, having thefollowing disadvantages: 1) The structure of produced polymer isuncontrollable; 2) It is difficult to adjust the molecular weight ofproduced polymer and to obtain high-molecular weight polymer; 3) Theproduced polymer loses high regularity, lowering solubility againstsolvent; and 4) Remaining low-molecular weight components may adverselyaffect the heat resistance and mechanical property of polymer.

[0010] A conventional process for preparing polyorganosilsesquioxaneusing trialkoxysilane is also advantageous from the viewpoint ofhandling convenience, such as controllability of a hydrolysis rate,compared to trichlorosilane. However, various studies reported that thisprocess had the following disadvantages caused by the oligomer moleculardeformity due to the presence of inter-hydroxy group, and by thepresence of alkoxy group: 1) A polymer of a branch structure, ratherthan a ladder structure, is formed; 2) selection of catalyst used,amount of the selected catalyst, selection of reactant solvent, carefuladjustment of pH of selected reactant solvent, and so on, are not easyto achieve; and 3) a three-dimensional network structure causesmicro-gelation. These disadvantages may adversely affect preparation ofhighly regular silicon ladder-form polymer.

[0011] As described above, a great attention has been paid topolyorganosilsesquioxane and constant research into the same has beenmade.

[0012] According to known various synthesizing methods, e.g., a sol-gelmethod, a ring-opening polymerization method or an equilibriumpolymerization method, and research into the structure ofpolyorganosilsesquioxane, condensation thereof is very complicated andversatile, so that the structure of polymer cannot be sufficientlycontrolled. Thus, even a product commercially available in the tradename of glass resin, also called T-type resin, cannot meet severalrequirements to be used as a novel industrial material, which becomesimpediment to practical use.

[0013] Requirements of novel industrial materials using organic orinorganic hybrid materials are: a low dielectric constant of 2 to 3;excellent thermal stability such as a pyrolysis starting temperature of400° C. or higher; low hygroscopicity; a low thermal expansioncoefficient; excellent gap filling capability; excellent bondability.

[0014] To overcome the above-described problems, the present inventorsproposed polyphenylsilsesquioxane having high regularity andcrystallinity, which cannot be controlled by conventionalmethods(sol-gel method), using high-purity organosilanetriol as astarting material, rather than oligomer having various molecular weightsand structures.

[0015] However, there is still a need for polyorganosilsesquioxanehaving high regularity/crystallinity.

SUMMARY OF THE INVENTION

[0016] It is an objective of the present invention to provide a novelhigh-technology inorganic material having excellent properties throughdevelopment of new precursors, and preparation method thereof, theprecursors being: 1) easy in handling; 2) capable of adjusting the rateof polymerization; 3) capable of uniformly distributing hydroxy groupsat both ends of polymer; 4) capable of introducing R—SiO₃/₂ to the mainchain of polymer with high regularity; 5) easily capable of adjustingthe crosslinking structure of polymer, specifically, crosslinkablity orcrosslinking density; 6) capable of facilitating chemical modificationby spreading the structure of polymer; 7) easily capable of formingnano-sized pores in the backbone of polymer; and 8) capable of impartinghigh functionality and versatile properties to polymer.

[0017] To accomplish the above objective of the present invention, thereis provided polyorganosilsesquioxane and a process for preparing thesame.

[0018] Polyorganosilsesquioxane according to the present invention is acompound represented by formula 1:

[0019] wherein R₁ and R₂ are independently a hydrogen atom, anunsubstituted or substituted aliphatic hydrocarbon group having 1 to 30carbon atoms, an unsubstituted or substituted aromatic hydrocarbon grouphaving 1 to 30 carbon atoms, an unsubstituted or substituted alicyclichydrocarbon group having 1 to 30 carbon atoms, an unsubstituted orsubstituted silyl group having 1 to 30 carbon atoms, an unsubstituted orsubstituted allyl group having 1 to 30 carbon atoms, an unsubstituted orsubstituted acyl group having 1 to 30 carbon atoms, a vinyl group, anamine group, an acetate group or an alkali metal, and n is an integer of2 to 300,000.

[0020] In the present invention, 1,3-diorganorsiloxane represented byformula 2 is provided as a precursor for preparing thepolyorganosilsesquioxane represented by Formula 1:

[0021] wherein R₁ and R₂ are as defined above, R₃ is a hydrogen atom, alower alkyl group, acetate, sodium or potassium, and X represents ahydrogen atom, a halogen atom, a hydroxy group, an amine group or acarboxy group.

[0022] The process for preparing the polyorganosilsesquioxane accordingto the present invention can be expressed in the reaction scheme 1:

[0023] wherein R₁, R₂ and R₃ are as defined above, and n and X are asdefined above.

[0024] The step (A) of the reaction scheme 1 is a step for preparing thecompound which is a precursor for preparing polyorganosilsesquioxane ofthe present invention, represented by Formula 1, the precursorrepresented by Formula 2. In step (A), a compound represented by Formula4, e.g., trichloromethylsilane, and a compound represented by Formula 3,e.g., trimethoxyphenylsilane, which are used as starting materials, arereacted in the presence of acidic catalyst or without catalyst, therebyeasily preparing various kinds of compounds represented by Formula 2.

[0025] The organic solvent used in the above reaction is notspecifically limited as long as it can be generally used in the art, butTHF, benzene, anisol, chlorobenzene, xylene, methylisobutylketone(MIBK), dimethylformamide (DMF), N-methylpyrrolidone (NMP), 1,4-dioxane,dimethylacetamicle (DMAC), acetone, or toluene is preferably used.

[0026] As the catalyst used in the above reaction, HCI, acetone,triethylamine, tin, pyridine, trichloroacetic acid or an aceticacid-amine complex catalyst is preferably used, and specifically,trichloroacetic acid is more preferably used from the viewpoint ofreaction rate, temperature and yield.

[0027] The reaction temperature is preferably 30 to 350° C., and thereaction time is preferably 1 to 300 hours.

[0028] The compound represented by Formula 2 obtained as a precursor, ispolymeric-condensed in an organic solvent, as represented by the step(B) of the reaction scheme 1 by the conventional method, therebyobtaining the polyorganosilsesquioxane represented by Formula 1.

[0029] The polymeric-condensation method used in step (B) of thereaction scheme 1 is not specifically limited, and various methodsincluding heating, light radiation, electron beam scanning, microwaveradiation and the like may be used. In the case of adding a catalyst, acompound having a large value of n can be obtained.

[0030] The compound used in step (B) of the reaction scheme 1 ispreferably in the range of 5 to 300 parts by weight, preferably 10 to100 parts by weight based on 100 parts by weight of organic solvent. Ifthe amount of the compound represented by Formula 2 is less than 5 partsby weight, the polymeric-condensation may be retarded or the reaction isnot fully carried out, and if greater than 300 parts by weight, gelationmay undesirably occur during reaction.

[0031] The catalyst used for facilitating the polymeric-condensation instep (B) of the reaction scheme 1, is not specifically limited, but atleast one material selected from the group consisting of alkali metalhydroxides such as sodium hydroxide, potassium hydroxide or cesiumhydroxide, amines such as triethylamine, diethylene triamine,meth-butylamine, para-dimethylamine ethanol, triethanol amine, orquaternary ammonium salts, and fluorides. The catalyst used forpolymeric-condensation is preferably in the range of 0.001 to 5 parts byweight, more preferably 0.001 to 1 part by weight based on 100 parts byweight of the compound represented by Formula 2.

[0032] In particular, in the case of using alkali metal hydroxide as acatalyst, it is preferred that the compound represented by Formula 2 ishydrolyzed in advance to thus produce a hydrolyzed product andpolymeric-condensation is then carried out.

[0033] The organic solvent used in step (B) of the reaction scheme 2 isnot specifically limited, and an organic solvent having a boiling pointof 100° C. or higher, such as toluene or NMP, is preferably used.

[0034] In step (B) of the reaction scheme 1, the reaction temperature ispreferably 50 to 350° C., more preferably 100 to 200° C. The reactiontime is preferably 1 to 50 hours in the case of using a catalyst. In thecase of not using any catalyst, the reaction temperature is preferably150 to 350° C., and the reaction time is preferably 1 to 200 hours. Ifthe reaction temperature is out of this range, the efficiency of thepolymeric-condensation cannot meet industrial requirement.

[0035] Also, if the purity of the compound represented by Formula 2 forpolymeric-condensation, is greater than or equal to 90%, a highmolecular weight polymer, that is, M_(n)>500,000, can be obtained by thephase transition method.

[0036] The polyorganosilsesquioxane represented by Formula 1 accordingto the present invention has a high solubility to a general organicsolvent, and is soluble in organic solvents including aromatichydrocarbons such as toluene, xylene, benzene or chlorobenzene,hydrocarbons such as methylene chloride or chloroethane, ethers such asTHF, 1,4-dioxane, diethylether or dibutylether, ketones such as acetone,methyethylketone or methyletherketone, esters, or dimethylformamide.

[0037] In the present invention, R₁ and R₂ are independently a hydrogenatom, an unsubstituted or substituted aliphatic hydrocarbon group having1 to 30 carbon atoms, an unsubstituted or substituted aromatichydrocarbon group having 1 to 30 carbon atoms, an unsubstituted orsubstituted alicyclic hydrocarbon group having 1 to 30 carbon atoms, anunsubstituted or substituted silyl group having 1 to 30 carbon atoms, anunsubstituted or substituted allyl group having 1 to 30 carbon atoms, anunsubstituted or substituted acyl group having 1 to 30 carbon atoms, avinyl group, an amine group, an acetate group or an alkali metal,preferably a lower alkyl such as a hydrogen atom, a methyl group, anethyl group or a propyl group, a phenyl group, a phenol group, achlorophenyl group, vinyl group, carboxyl group, a trimethylsilyl group,acetate or alkali metal, and more preferably a hydrogen atom, a methylgroup, a vinyl group or a trimethylsilyl.

[0038] As described above, according to the present invention, unlike inconventional polyorganosilsesquioxane obtained by heat-condensingoligomer prepared by hydrolyzing conventional trichlorosilane ortriethoxysilane, a silane-based compound is first reacted as a startingmaterial to obtain 1,3-diorganosiloxane, which is a precursor, and thenpolymeric-condensed to obtain polyorganosilsesquioxane, therebysynthesizing a highly-regular ladder-form polymer having repeating unitsof cyclotetraorganosilsesquioxane.

[0039] As described above, since Si—O—Si bonds and ladder-formstructures are easily formed in the main chain of polymer with highregularity, high-heat-resistance can be maintained. Also, sinceinter-hydroxy group structures or defects existing in the main chain ofpolymer can be reduced, no thermal treatment is required and variousfunctional side chains (e.g., a photosensitive group or dealkyl reactivegroup) can be introduced. In particular, the physical property ofpolymer depending on a composition ratio of the introduced side chains,e.g., a difference in the ratio of phenyl to methyl, can be changed, andnew polymeric molecules can be designed. Since terminal-silanol groupscan be arranged regularly at the terminal of polymer so that the amountof organic polymer introduced can be adjusted in preparing organic orinorganic hybrid materials, thereby easily preparing an organic orinorganic copolymer.

[0040] In particular, the polyorganosilsesquioxane prepared according tothe present invention has a unique molecular structure, that is, theratio of siloxane (Si—O—Si) bonds and rigid ladder-form structures(R—SiO_(3/2)) present in the main chain of the polyorganosilsesquioxaneprepared according to the present invention is 97% more than in theconventional polyorganosilsesquioxane, the percentage being representedby

[0041] {No.of R—SiO_(3/2))÷(No.of hydroxygroups+No.of terminal−silanolgroups)×100}.

[0042] Thus, the polyorganosilsesquioxane prepared according to thepresent invention exhibits high solubility to a general organic solvent,and has excellent anti-wearability, low surface tension, opticaltransparency, low dielectric constant of 3.0 or less, low absorptionratio, excellent gap filling capability and so on. Also, thepolyorganosilsesquioxane prepared according to the present invention isexcellent in view of adhesion to glass or metal, e.g., aluminum, copper,titanium or silicon, electric insulation, water drainage, chemicalresistance or transparency, by introducing different side chains, andcan be commercially applicable in a wide range of industrial materials.

[0043] The polyorganosilsesquioxane prepared according to the presentinvention can be used in various fields: UV curable resins and silanecompounds are widely used; and glass resins are also used in somefields. Materials of the polyorganosilsesquioxane prepared according tothe present invention include polycarbonate, acryl resin,diethylglycolbisalkylcarbonate (in the trade name of “CR-39”) and so on.The polyorganosilsesquioxane prepared according to the present inventioncan be used for plastic, sunglasses, protective glasses, dash board,automobile lamps, aircraft windows or bulletproof glass. Also, thepolyorganosilsesquioxane prepared according to the present invention canbe used for thermally treating glass lenses with glass resin.

[0044] Further, the polyorganosilsesquioxane prepared according to thepresent invention is excellent in view of electric insulation, heatresistance, low absorption, planarization of a spin-on glass (SOG)solution, thereby being adapted to electronic usage. For example, thepolyorganosilsesquioxane prepared according to the present invention isa general-purpose material that can be used as a protective coating fora thin film, an interlayer dielectric film in LSI multiple layer wiring,a low dielectric material, a multiple insulation film, an LCD insulatorfilm and the like.

[0045] Recently, as a highly integrated semiconductor device has becomenarrower in line space, the thickness of formed coating layersunavoidably increase, resulting in cracks. Generation of cracks ispresumably caused by the following factors: 1) thermal curingcontraction stress generated when inter-hydroxy groups orterminal-silanol groups are mutually condensed; and 2) a difference inthermal stress depending on a difference in the thermal expansioncoefficient among a cured film, an aluminum wiring and a silicon wafer.In the present invention, since the presence ratio of inter-hydroxygroups is low due to a defective structure of polymer, that is less thanor equal to 5%, a reaction occurring at the terminal can be prevented byintroducing silylation or double bond into the terminal-silanol group,and new functionality of an organic-inorganic hybrid material can beattained by introducing other organic polymer, specifically polyimide,polyamide, PMMA, polyacryl, polycarbonate, polystyrene or polyurethane.

[0046] Further, the polyorganosilsesquioxane prepared according to thepresent invention is soluble in various solvents to form a thin filmeasily and has a high level of hardness of 4 to 8H. Also, since thepolyorganosilsesquioxane prepared according to the present invention canform a highly transparent thin film, it can be commercialized togetherwith optically functional organic polymers, thereby increasing thelong-term reliability of optical fiber. Also, since thepolyorganosilsesquioxane prepared according to the present invention isused as a material for forming a coating on the surface of a resistor,it can be applied for electric/electronic materials.

[0047] Also, the polyorganosilsesquioxane prepared according to thepresent invention can be used as a metal release agent in plasticmolding plastic, e.g., urethane reactive injection molding (RIM), or inmanufacturing glass. Further, a mixture of RTV and thepolyorganosilsesquioxane prepared according to the present invention canbe used as a tile adhesive agent or outer surface coating of a spaceshuttle, a binder of optical fiber, and the like, and can be used forheat-resistive coating materials owing to its heat resistance andcorrosion resistance.

[0048] The applicability of the final product according to the presentinvention will be boundlessly extended, not limited to theabove-described fields, along with the development of advancedtechnology.

DETAILED DESCRIPTION OF THE INVENTION

[0049] For better understanding of the present invention, the inventionwill now be described in detail through preferred embodiments withreference to the accompanying drawings. The present invention may,however, be embodied in different forms and should not be construed aslimited to the embodiments set forth herein. Rather, those embodimentsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the invention to those skilled in theart.

EXAMPLE 1 Preparation of a Compound Represented by Formula 1;(1,1-dichloromethyl-3,3-diethoxyphenylsiloxane) (R₁=methyl, R₂=phenyl)

[0050] A reflux condenser and a 100 ml dropping funnel were placed in a500 ml three-necked round bottom flask and dried with flame under anitrogen atmosphere. 19.8 ml of trimethoxyphenylsilane and 1.6 ml ofCCl₃COOH were dissolved in acetone and stirred for 4 hours. Thereafter,15 ml of trichloromethylsilane was slowly dropped by a dropping funneland reacted at room temperature for 72 hours. Thereafter, a vacuumdistillation device was installed in the reaction system tovacuum-remove unreacted trimethyoxysi lane, trichlorosilane andCCl₃COOH, thereby obtaining a white, clear solution (yield: 86%).

[0051]¹H NMR (500 MHz/CDCl₃): δ0.2 (s, Si—Me), 3.5 (s, Si—OMe), 7.2˜7.8(d, Si—Ph) ppm

[0052]²⁹Si NMR (99.3 MHz/CDCl₃): δ−7.5 (s, Si—OCH₃), −24.8 (s, Si—Cl)ppm

[0053] GC/Mass spectrometry: M_(n)=296

EXAMPLE 2 Hydrolysis of a Compound Represented by Formula 2;(1,1-dichloromethyl-3,3-diethoxyphenylsiloxane)

[0054] A reflux condenser and a 100 ml dropping funnel were placed in a500 ml three-necked round bottom flask and dried with flame under anitrogen atmosphere. 30 ml of(1,1-dichloromethyl-3,3-diethoxyphenylsiloxane) prepared in Example 1was dissolved in 70 ml toluene and then transferred to a droppingfunnel. 350 ml of tertiary distilled water and HCI were put into a 500ml round bottom flask to make the solution pH 2.5, and then1,1-dichloromethyl-3,3-diethoxyphenylsiloxane was slowly dropped throughthe dropping funnel to be hydrolyzed at 3° C. After hydrolysis, anorganic layer and an aqueous layer were separated using a separatingfunnel, and the aqueous layer was recrystallized at 3° C. to obtainwhite, clear powder of hydrolyzed product Ph(OH)₂SiOSiMe(OH)₂ (yield:88%).

[0055] The white powder was low-temperature dried at 3° C. to be used asan analysis sample.

[0056]¹H NMR (500 MHz/CDCI₃): δ0.8 (s, Si—Me), 2.7˜3.25 (s, Si—OH),7.3˜7.78 (d, Si—Ph) ppm; Si—Me/Si—OH/Si—Ph=25.77/23.18/16.36=3/4/5

[0057] LC/Mass spectrometry: M_(n)=295.9

EXAMPLE 3 Polymeric-Condensation of Hydrolyzed Product(Ph(OH)₂SiOSiMe(OH)₂)

[0058] A Dean Stark tube was installed in a 50 ml round bottom flask anddried with flame under a nitrogen atmosphere. 10 g of the hydrolyzedproduct (Ph(OH)₂SiOSiMe(OH)₂) obtained in Example 2 and 0.1 g of KOHwere put into the flask, and 38 ml of toluene was added thereto todissolve the hydrolyzed product (Ph(OH)₂SiOSiMe(OH)₂). Subsequently, theresultant was reacted at a reflux temperature of toluene for 18 hours.After reaction, the reactant was dropped to an excess of methanol andagitated for 30 minutes to filter the precipitate, thereby obtainingwhite powder of a desired product (yield: 98%).

[0059] The product was vacuum-dried at 50° C. for 10 hours to be used asan analysis sample.

[0060]¹H NMR (500 MHz/CDCl₃): δ−0.5˜0.8 (s, Si—Me), 7.11˜7.8 (s, Si—Ph)ppm; 3080˜2940 (CH), 1435 (Si—Ph), 1050 (O—Si—Ph), 1150 (O—Si), 750, 700(Ph)cm⁻¹,

[0061]²⁹Si NMR (99.3 MHz/CDCl₃): δ−67.7 (Me-T₃), −83.7 (Ph-T₃) ppm

[0062] GPC(PST); M_(n)=35,244

[0063] Td=480° C.

[0064] DC (degree of crosslinking) (%); T₃/T_(total)×100=98%

[0065] Low k=2.72

[0066] While the present invention has been described in conjunctionwith the preferred embodiments, these embodiments are presented forillustrative purposes only, and are not intended as a restriction on thescope of the invention as recited in the appended claims.

What is claimed is:
 1. A compound represented by Formula 1:

wherein R₁ and R₂ are independently a hydrogen atom, an unsubstituted orsubstituted aliphatic hydrocarbon group having 1 to 30 carbon atoms, anunsubstituted or substituted aromatic hydrocarbon group having 1 to 30carbon atoms, an unsubstituted or substituted alicyclic hydrocarbongroup having 1 to 30 carbon atoms, an unsubstituted or substituted silylgroup having 1 to 30 carbon atoms, an unsubstituted or substituted allylgroup having 1 to 30 carbon atoms, an unsubstituted or substituted acylgroup having 1 to 30 carbon atoms, a vinyl group, an amine group, anacetate group or an alkali metal, and n is an integer of 2 to 300,000.2. The compound according to claim 1, wherein R₁ and R₂ areindependently a hydrogen atom, a methyl group, a vinyl group or atrimethylsilyl group, and n is an integer from 1,000 to 100,000.
 3. Acompound represented by Formula 2:

wherein R₁ and R₂ are independently a hydrogen atom, an unsubstituted orsubstituted aliphatic hydrocarbon group having 1 to 30 carbon atoms, anunsubstituted or substituted aromatic hydrocarbon group having 1 to 30carbon atoms, an unsubstituted or substituted alicyclic hydrocarbongroup having 1 to 30 carbon atoms, an unsubstituted or substituted silylgroup having 1 to 30 carbon atoms, an unsubstituted or substituted allylgroup having 1 to 30 carbon atoms, an unsubstituted or substituted acylgroup having 1 to 30 carbon atoms, a vinyl group, an amine group, anacetate group or an alkali metal, R₃ is a hydrogen atom, a lower alkylgroup, acetate, sodium or potassium, and X represents a hydrogen atom, ahalogen atom, a hydroxy group, an amine group or a carboxy group.
 4. Thecompound according to claim 1, wherein R₁ and R₂ are independently ahydrogen atom, a methyl group, a phenyl group or a trimethylsilyl group,R₃ is a hydrogen atom, a methyl group, acetate, sodium or potassium, andX represents a hydrogen atom, chlorine, a hydroxy group, an amine groupor a carboxy group.
 5. A process for preparing a compound represented byFormula 1 obtained by polymeric-condensing a solution of a compoundrepresented by Formula 2 in an organic solvent:

wherein R₁ and R₂ are independently a hydrogen atom, an unsubstituted orsubstituted aliphatic hydrocarbon group having 1 to 30 carbon atoms, anunsubstituted or substituted aromatic hydrocarbon group having 1 to 30carbon atoms, an unsubstituted or substituted alicyclic hydrocarbongroup having 1 to 30 carbon atoms, an unsubstituted or substituted silylgroup having 1 to 30 carbon atoms, an unsubstituted or substituted allygroup having 1 to 30 carbon atoms, an unsubstituted or substituted acylgroup having 1 to 30 carbon atoms, a vinyl group, an amine group, anacetate group or an alkali metal, R₃ is a hydrogen atom, a lower alkylgroup, acetate, sodium or potassium, X represents a hydrogen atom, ahalogen atom, a hydroxy group, an amine group or a carboxy group, n isan integer of 2 to 300,000.
 6. The process according to claim 5, whereinthe polymeric-condensing reaction is one selected from the groupconsisting of heating, light radiation, microwave radiation and electronbeam radiation.
 7. The process according to claim 5, wherein the amountof the compound represented by Formula 2 is 5 to 300 parts by weightbased on 100 parts by weight of the organic solvent.
 8. The processaccording to claim 5, wherein the process is further performed in thepresence of a polymeric-condensation catalyst.
 9. The process accordingto claim 8, wherein the polymeric-condensation catalyst is one selectedfrom the group consisting of sodium hydroxide, potassium hydroxide,cesium hydroxide, triethylamine, diethylene triamine, meth-butylamine,para-dimethylamine ethanol, triethanol amine, quaternary ammonium salts,and fluorides.
 10. The process according to claim 8, wherein thecatalyst used for polymeric-condensation is preferably in the range of0.001 to 5 parts by weight, based on 100 parts by weight of the compoundrepresented by Formula
 4. 11. A process for preparing a compoundrepresented by Formula 2 by reacting a compound represented by Formula 3and a compound represented by Formula 4:

wherein R₁, R₂ and R₃ are as defined in claim 1 or 2.